Snowplow and mount assembly

ABSTRACT

A snowplow and mount assembly comprising a mount frame adapted to be secured to a vehicle, and a snowplow frame. One of the mount frame and the snowplow frame has first and second arms and the other of the mount frame and snowplow frame has first and second receivers, the first and second receivers receiving the first and second arms, respectively. Respective ones of first and second latch pins removably secure the first and second arms in the first and second receivers. A latch lever is operably associated with the first and second latch pins and simultaneously actuates the latch pins to latched and unlatched positions. The snowplow frame includes a jack stand movable to and between an extended ground contacting and snowplow frame supporting position and a retracted ground noncontacting and snowplow frame nonsupporting position. The latch lever operably frees the jack stand for movement into the extended position when the latch pins are in the unlatched position and operably prevents jack stand movement maintaining the jack stand in the retracted position when the latch pins are in the latched position.

FIELD OF THE INVENTION

This invention relates generally to snow removal equipment and, moreparticularly, to a snowplow and mount assembly for removably securing asnowplow to a vehicle.

BACKGROUND OF THE INVENTION

It is desirable to provide a snow plow assembly with a mechanismaffording attachment to and detachment from a vehicle. The vehicleoperator may wish to remove the snow blade during times when the needfor plowing snow arises infrequently or when the vehicle is used forpurposes other than plowing snow.

To that end the assignee of the present invention obtained U.S. Pat. No.5,353,530, hereby incorporated by reference herein as if fully set forthin its entirety. That patent discloses a mount frame having arms and asnowplow frame having receivers which receive the arms. The snowplowframe includes a lift frame and an A-frame pivoted to the lift frame.The receivers are formed as a part of the lift frame. The receiverscarry latch pins which are spring biased toward a latching position yetwhich are lockable in an unlatched position. When the arms of the mountframe have been driven into the receivers of the lift frame each of thelatch pins are individually released; the bias of the springs drives thepins through holes in the receivers and in the arms thereby latching thelift frame and hence snowplow to the mount frame and hence vehicle. Ajack stand is carried by the lift frame and is manually movable to andbetween an extended ground contacting and snowplow supporting positionand a retracted ground noncontacting and snowplow nonsupportingposition.

It is desirable to improve upon the invention of U.S. Pat. No. 5,353,530by providing a snowplow and mount assembly which facilitates moreefficient latching of the latch mechanism removably securing thesnowplow to the mount and which facilitates more efficient deployment ofthe jack stand of the snowplow.

SUMMARY OF THE INVENTION

In one aspect the invention is a snowplow and mount assembly comprisinga mount frame adapted to be secured to a vehicle, and a snowplow frame.One of the mount frame and the snowplow frame has first and second armsand the other of the mount frame and snowplow frame has first and secondreceivers, the first and second receivers receiving the first and secondarms, respectfully. Respective ones of first and second latch pinsremovably secure the first and second arms in the first and secondreceivers. A latch lever is operably associated with the first andsecond latch pins and simultaneously actuates the latch pins to latchedand unlatched positions.

The assembly can further comprise a spring biasing each latch pin intothe latched position and a pin extractor associated with each latch pinand actuatable by the latch lever to extract the latch pin from thelatch arm against the bias of the spring. The extractor can include acam which operably cams against the latch pin during the extractionthereof. The latch pin and respective extractor can be mounted inbrackets mounted to the snowplow frame, the brackets guiding movement ofthe latch pin and extractor. The latch pins can travel transverselyrelative to a longitudinal axis of the assembly and the extractors cantravel perpendicularly relative to the travel of the pins. The latch pincan include a cross pin therethrough which can compress the springagainst a wall of the bracket as the cam cams against the cross pin. Thecam surface can be a ramp.

The latch lever can be pivotally connected to the snowplow frame, andthe assembly can further include first and second linkages connectedbetween the latch lever and the extractors. Each of the first and secondlinkages can include a linkage arm connected to the latch lever, and alinkage rod pivotally connected on a first end to the linkage arm andconnected on a second end to the extractor. The latch lever can includea connecting rod extending transversely of the snowplow frame, with thefirst and second linkages being connected to the connecting rod.

The first and second arms can be part of the mount frame and the firstand second receivers can be part of the snowplow frame. The snowplowframe can comprise a lift frame and an A-frame pivotally connected tothe lift frame on a rearward end of the A-frame. The assembly canfurther comprise a plow blade mounted on a forward end of the A-frame.

In another aspect the invention is a snowplow and mount assemblycomprising a mount frame adapted to be secured to a vehicle and asnowplow frame including a jack stand movable to and between an extendedground contacting and snowplow frame supporting position and a retractedground noncontacting and snowplow frame nonsupporting position. A latchmechanism removably secures the snowplow frame to the mount frame. Alatch lever actuates the latch mechanism to latched and unlatchedpositions, the latch lever operably freeing the jack stand for movementinto the extended position when the latch mechanism is in the unlatchedposition and operably preventing jack stand movement maintaining thejack stand in the retracted position when the latch mechanism is in thelatched position.

The assembly can further comprise first and second jack stand locks, thefirst lock preventing relative movement of the jack stand relative tothe snowplow frame when the jack stand is in the extended position andthe second lock preventing relative movement of the jack stand relativeto the snow plow frame when the jack stand is in the retracted position.The first jack stand lock can comprise a jack stand lock lever having anaperture therein through which a leg of the jack stand passes and aspring biasing an edge of the lock lever aperture into contact with thejack stand leg. The spring and lock lever normally prevent upwardmovement of the jack stand relative to the snowplow frame whilepermitting downward movement of the jack stand relative to the snowplowframe, whereas pivoting the lock lever against the bias of the springfrees the jack stand leg from the lock lever aperture edge permittingupward movement of the jack stand relative to the snowplow frame.

The second jack stand lock can comprise a jack stand lock pin moveableinto and out of an aperture in a leg of the jack stand and a springbiasing the lock pin toward the jack stand leg. The spring and lock pinnormally prevent downward movement of the jack stand relative to thesnowplow frame, whereas urging the lock pin against the bias of thespring frees the jack stand leg from the pin permitting downwardmovement of the jack stand relative to the snowplow frame. The jackstand can drop by gravity to the extended position when the jack standleg is freed from the pin.

The latch lever can include a cam operably connected thereto and thejack stand lock pin can be fixed to a cam follower which cooperates withthe cam such that pivoting the latch lever to actuate the latchmechanism to the unlatched position urges the cam follower and hence thejack stand lock pin against the bias of the spring and away from thejack leg and out of the aperture thereof, whereas pivoting the latchlever to actuate the latch mechanism to the latched position permits thespring to bias the jack stand lock pin toward the jack stand leg andinto the aperture thereof.

The latch lever can include a connecting rod extending transversely ofthe snowplow frame, the cam can be a cylinder encircling the connectingrod affixed thereto and the cam follower can be a cylinder encirclingthe connecting rod and a slidable relative thereto. The cam cylinder andcam follower cylinder can have mating arcuate surfaces.

In further aspects the invention provides methods of attaching asnowplow frame to and detaching a snowplow frame from a mount frame. Amethod of attaching a snowplow frame to a mount frame comprisesproviding a mount frame secured to a vehicle and a snowplow frame, oneof the mount frame and the snowplow frame having first and second armsand the other of the mount frame and the snowplow frame having first andsecond receivers, the first and second receivers receiving the first andsecond arms, respectively, one of the mount frame and the snowplow framehaving first and second latch pins, respective ones of which removablysecure the first and second arms in the first and second receivers, anda lever operably associated with the first and second latch pins tosimultaneously actuate the latch pins to a latched position, effectingrelative movement between the mount frame and the snowplow frame so thatthe receivers receive the arms therein and actuating the lever tosimultaneously actuate the pins to the latched position.

A method of detaching a snowplow frame from a mount frame comprisesproviding a mount frame secured to a vehicle and a snowplow frameremovably attached to the mount frame, one of the mount frame and thesnowplow frame having first and second arms and the other of the mountframe and the snowplow frame having first and second receivers, thefirst and second receivers receiving the first and second arms,respectively, one of the mount frame and the snowplow frame having firstand second latch pins, respective ones of which removably secure thefirst and second arms in the first and second receivers, and a leveroperably associated with the first and second latch pins tosimultaneously actuate the latch pins to an unlatched position,actuating the lever to simultaneously actuate the latch pins to theunlatched position and effecting relative movement between the mountframe and the snowplow frame so that the arms move out of the receivers.

Another method of detaching a snowplow frame from a mount framecomprises providing a mount frame secured to a vehicle and a snowplowframe removably attached to the mount frame, the snowplow frameincluding a jack stand moveable to and between an extended groundcontacting and snowplow frame supporting position and a retracted groundnoncontacting and snowplow frame nonsupporting position, one of themount frame and the snowplow frame having a latch mechanism whichremovably secures the snowplow frame to the mount frame and a leverwhich actuates the latch mechanism to an unlatched position and whichfrees the jack stand for movement into the extended position, actuatingthe lever to actuate the latch mechanism to the unlatched position andto free the jack stand to drop by gravity to the extended position, andeffecting relative movement between the mount frame and the snowplowframe to separate the mount frame from the snowplow frame.

The invention thus provides for the simultaneous latching and unlatchingof the latch pins of a snowplow and for the automatic deployment of thesnowplow jack stand during unlatching of the latch mechanism of thesnowplow.

These and other features and advantages of the present invention willbecome more readily apparent during the following detailed descriptiontaken in conjunction with the drawings herein, in which:

BRIEF DESCRIPTION OF THE DRAWINGS OF THE INVENTION

FIG. 1 is a side view of the snowplow and mount assembly of the presentinvention;

FIG. 2 is a rear perspective view of the snowplow assembly of FIG. 1;

FIG. 3 is an enlarged rear perspective view of the right hand receiverand its respective latch pin;

FIG. 4 is an enlarged rear view of the jack stand lock which preventsrelative movement of the jack stand relative to the snowplow frame whenthe jack stand is in the extended position, shown unlocked;

FIG. 5 is an enlarged rear perspective view of the jack stand lock whichprevents relative movement of the jack stand relative to the snowplowframe when the jack stand is in the retracted position, shown unlocked;and

FIG. 6 is the jack stand lock of FIG. 5, shown locked.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

Referring first to FIGS. 1 and 2 there is illustrated a snowplow andmount assembly 10 according to the principles of the present invention.Snowplow and mount assembly 10 comprises a snowplow assembly 12 and amount assembly 14. Snowplow assembly 12 can comprise a snowplow frame 20having a lift frame 22 and an A-frame 24 pivoted to the lift frame 22.A-frame 24 can be pivotally connected to lift frame 22 on a rearward end26 of the A-frame 24 such as by bolt 28 for example. A forward end 30 ofthe A-frame 24 can carry a plow blade 32. A-frame 24 can comprise leftand right hand A-frame elements 34, 36, respectively, and a transverseelement 38 interconnecting left and right hand A-frame elements 34, 36.

Lift frame 22 can comprise left and right hand upwardly extendingelements 40, 42, respectively, interconnected at their upper ends bytransversely extending element 44. Another transversely extendingelement 46 can interconnect the elements 40, 42 generally medially ofthe height extent of the elements 40, 42. Transversely extending element46 can include top 48 and bottom 50 plates.

The lower ends of elements 40, 42 of lift frame 22 can include receivers52, 54, respectively. Left hand receiver 52 can include sidewalls 56, 58having outwardly flared end portions 60, 62, respectively. A floor 64can interconnect the sidewalls 56, 58. Similarly, right hand receiver 54can include sidewalls 66, 68 having outwardly flared end portions 70,72, respectively. A floor 74 can interconnect the sidewalls 66, 68.

Lift frame 22 can include a lift arm 80 pivoted to transverselyextending element 44. A lift chain 82 and spring 84 can connect the liftarm 80 to the A frame 24. Alternatively a flexible wire rope cable canbe used in place of the lift chain 82. A lift cylinder 86 can bepivotally mounted to the lift arm 80 and transversely extending element46 of the lift frame 22, for raising and lowering lift arm 80 and henceA-frame 24 and plow blade 32. Head light 88 can be mounted totransversely extending element 44.

Referring now back to FIG. 1, mount assembly 14 can comprise a mountframe 90 adapted to be secured to a vehicle (phantom) having a pair ofspaced arms 92, 92. Arms 92, 92 are receivable in the receivers 52, 54of lift frame 22. Each arm 92 includes a latch pin receiving hole 94therein, the operation of which will be described below.

Referring now to FIGS. 1 through 3, a latch mechanism 100 can removablysecure the snowplow frame 20 to the mount frame 90. Latch mechanism 100can comprise first and second latch pins 102, 104 associated withreceivers 52, 54, respectively. Latch pin 102 is operable to passthrough hole 110 in sidewall 56, hole 94 in arm 92 and hole 112 insidewall 58, when arm 92 is received within receiver 52. Similarly,latch pin 104 is operable to pass through hole 120 in sidewall 68, hole94 in the other arm 92 and hole 122 in sidewall 66, when the other arm92 is received within receiver 54. A bracket 130 can be mounted to theoutboard side of sidewall 56 of receiver 52 to carry latch pin 102therein. A spring 132 can bias latch pin 102 into the latched position.More particularly, a cross pin 134, for example roll pin, can be pressedthrough a hole (not shown) in latch pin 102. Spring 132 can be disposedbetween cross pin 134 and an inboard surface of end plate 136 of bracket130. Similarly, a bracket 140 can be mounted to the outboard side ofsidewall 68 of receiver 54 to carry latch pin 104 therein. A spring 142can bias latch pin 104 into the latched position. More particularly, across pin 144, for example roll pin, can be pressed through a hole (notshown) in latch pin 104. Spring 142 can be disposed between cross pin144 and an inboard surface of end plate 146 of bracket 140.

Referring now to FIGS. 2 and 3, receivers 52, 54 can each include a pinextractor 150, 152 associated respectively therewith. Each extractor150, 152 can include a cam 154, 156, respectively, which can be in theform of a ramp, to cam against cross pins 134, 142, respectively, andhence operably against latch pins 102, 104, respectively, the operationof which will be described below.

A latch lever 160 can be operably associated with the first and secondlatch pins 102, 104 for simultaneously actuating the latch pins 102, 104to latched and unlatched positions. Latch lever 160 can include aconnecting rod 162 extending transversely of the lift frame 22 andpivotally connected thereto. First and second linkage mechanisms 164,166 can be connected to latch lever 160 for actuating the extractors150, 152 associated with latch pins 102, 104, respectively. Linkage 164can include a linkage arm 170 connected to connecting rod 162 and alinkage rod 172 pivotally connected on a first end to the linkage arm170 and connected on a second end to the extractor 150. Similarly,linkage 166 can include a linkage arm 180 connected to connecting rod162 and a linkage rod 182 pivotally connected on a first end to thelinkage arm 180 and connected on a second end to extractor 152.

In use, rotation of latch lever 160 counterclockwise (as viewed from theleft hand side shown in FIG. 1) from the up position (solid, FIG. 1) tothe down position (phantom, FIG. 1), as when detaching the snowplowassembly 12 from the mount assembly 14, actuates linkages 164, 166 topull extractors 150, 152 upwardly and frontwardly. The ramped cams 154,156 of the extractors 150, 152 force cross pins 134, 144 laterallyoutwardly against the bias of springs 132, 142 thus moving latch pins102, 104 laterally outwardly to their unlatched positions. Rotation oflatch lever 160 clockwise from the down position to the up position, aswhen attaching the snowplow assembly 12 to the mount assembly 14,actuates linkages 164, 166 to push extractors 150, 152 downwardly andrearwardly. The ramped cams 154, 156 of the extractors 150, 152 permitcross pins 134, 144 to move laterally inwardly via the bias of springs132, 142 thus moving latch pins 102, 104 laterally inwardly to theirlatched positions.

Referring now to FIGS. 1, 2 and 4-6, a jack stand 190 can be slidablymounted to lift frame 22. Jack stand 190 can include a leg 192 and afoot 194. Jack stand 190 is moveable to and between an extended groundcontacting and snowplow frame supporting position (solid, FIG. 1) and aretracted ground noncontacting and snowplow frame nonsupporting position(phantom, FIG. 1; FIG. 2). First 200 and second 202 jack stand locks canbe provided to prevent relative movement of the jack stand 190 relativeto the lift frame 22 when the jack stand 190 is in the extendedposition, and to prevent relative movement of the jack stand 190relative to the lift frame 22 when the jack stand 190 is in theretracted position, respectively.

First jack stand lock 200 can include a lock lever 210 pivoted to a wall212 of a bracket 214 mounted to top plate 48 of transverse element 46 oflift frame 22. Lock lever 210 can be pivoted to wall 212 as by passingan end 216 of lever 210 through aperture 218 in wall 212. Lock lever 210can have an aperture 220 therein through which jack stand leg 192passes, and a spring 222 positioned between lock lever 210 and top plate48 biasing edges 224, 226 of aperture 220 into contact with jack standleg 192. Lock lever 210 and bracket 214 are sized and configured so asto prevent inadvertent actuation thereof when snowplow assembly 12 isdetached from mount assembly 14.

Spring 222 and lock lever 210 normally prevent upward movement of jackstand leg 192 relative to lift frame 22 while at the same time freelypermitting downward movement of jack stand leg 192 relative to the liftframe 22. Pivoting lock lever 210 downwardly (FIG. 4) frees jack standleg 192 of edges 224, 226 of lock lever aperture 220 thereby permittingupward movement of the jack stand leg 192 relative to the lift frame 22.

Second jack stand lock 202 can include a lock pin 240 moveable into andout of an aperture 242 in jack stand leg 192 and a spring 244 biasinglock pin 240 toward the jack stand leg 192. The spring 244 and lock pin240 normally prevent downward movement of the jack stand 192 relative tothe lift frame 22, whereas urging the lock pin 240 against the bias ofthe spring 244 frees the jack stand leg 192 from the pin 240 permittingdownward movement of the jack stand 190 relative to the lift frame 22.The jack stand 190 can drop by gravity to the extended position when thejack stand leg 192 is freed from pin 240.

The second jack stand lock 202 can further include a cam 260 connectedto connecting rod 162 and a cam follower 262 having fixed thereto thelock pin 240. Cam 260 can be in the form of a cylinder encirclingconnecting rod 162 and fixed thereto and cam follower 262 can be in theform of a cylinder encircling connecting rod 162 and slidable relativethereto. Cam 260 and cam follower 262 can have mating arcuate, forexample helix, cam surfaces 264, 266, respectively. Cam follower 262 andhence lock pin 240 can be spring biased toward jack stand leg 192 viaspring 244 positioned between cam follower 262 and a plate 272 connectedbetween plates 48 and 50. Cam follower 262 and hence pin 240 can beprevented from rotating via U-bracket 274 fixed to plate 50 and havingarms 276, 276 with holes 278, 278 therein through which pin 240 passes.

As illustrated cam 260 is fixedly secured to connecting rod 162 and assuch will rotate with connecting rod 162 as latch lever 160 is rotated.Thus, in use, rotation of latch lever 160 counterclockwise (as viewedfrom the left hand side shown in FIG. 1) from the up position (solid,FIG. 1) to the down position (phantom, FIG. 1), as when detaching thesnowplow assembly 12 from the mount assembly 14, not only actuateslinkages 164, 166 to unlatch latch pins 102, 104 but also actuates cam260 to unlock pin 240. The spring rates of springs 132, 142, 222 and244, and the geometries of their associated mechanisms, can be selectedso that jack stand 190 falls by gravity to the ground during the firstportion of the arc traversed by lever 160 in moving lever 160 from theup position toward the down position, while latch pins 102, 104 remainlatched. Then, as lever 160 is moved the remaining portion of the arc tothe down position, latch pins 102, 104 are moved to their unlatchedpositions.

As described above rotation of latch lever 160 clockwise from the downposition to the up position, as when attaching snowplow assembly 12 tomount assembly 14, actuates linkages 164, 166 to move latch pins 102,104 to their latched positions. Once so latched, jack stand lock lever210 can be pressed downwardly freeing jack stand leg 192. Jack stand leg192 is then manually pulled upwardly until jack stand lock pin 240 isseated in aperture 242 in jack stand leg 192.

For both attaching the snowplow assembly 12 to and detaching thesnowplow assembly 12 from the mount assembly 14 a force should beapplied to the lift frame 22, such as on transverse element 44, in thedirection of the mount assembly 14 as latch lever 160 is rotated. Suchmovement facilitates alignment of the latch pins 102, 104 with the holes94 in the arms 92. This movement is possible because tension spring 84,extended during normal operation of snowplow assembly 12, retracts whensnowplow assembly 12 is parked, blade 32 is dropped to the ground andthe hydraulic control is placed in the “float” condition releasing thepressure in the lift cylinder 86, pulling lift arm 80 downwardly to itsfully collapsed positioned and creating slack in the lift chain 82.

Latch lever 160 and linkage mechanisms 164, 166 are designed so that themechanical advantage produced thereby is insufficient to unlatch“loaded” latch pins 102, 104, thus preventing the snowplow assembly 12from “collapsing in a heap.” In other words, and as discussed above,initial rotation of latch lever 160 permits jack stand 190 to fall bygravity and support the snowplow assembly 12. Further rotation of latchlever 160 to retract latch pins 102, 104 is not possible until liftframe 22 is pivoted relative to A-frame 24 and toward mount frame 90 tounload latch pins 102, 104. Jack stand 190 and jack stand foot 194 aresized, configured and located to permit such pivoting of lift frame 22relative to A-frame 24 without causing instability of the snowplowassembly 12 during such pivoting.

Those skilled in the art will readily recognize numerous adaptations andmodifications which can be made to the present invention which willresult in an improved snowplow and mount assembly, yet all of which willfall within the spirit and scope of the present invention as defined inthe following claims. Accordingly, the invention is to be limited onlyby the scope of the following claims and their equivalents.

1. A snowplow and mount assembly comprising: a mount frame adapted to besecured to a vehicle having a longitudinal axis; a snowplow frameincluding a lift frame and an A-frame pivotally connected to said liftframe on a rearward end of said A-frame; one of said mount frame andsaid lift frame having first and second arms and the other of said mountframe and said lift frame having first and second receivers, said firstand second receivers receiving said first and second arms, respectivelyupon relative movement therebetween in a direction generally parallel tothe longitudinal axis of the vehicle; first and second latch pinsnormally biased toward a latched position, respective ones of whichremovably secure said first and second arms in said first and secondreceivers; and a latch lever operably associated with said first andsecond latch pins for permitting both said latch pins to move to thelatched position and for moving both said latch pins to an unlatchedposition; a spring biasing each said latch pin into said latchedposition; a pin extractor associated with each said latch pin andactuatable by said latch lever to extract said latch pin from said armand against the bias of said spring; said extractor including a camwhich operably cams against said latch pin during extraction thereof;each said latch pin and respective extractor being mounted in bracketsmounted to said snowplow frame, said brackets guiding movement of saidlatch pin and extractor; wherein said latch pins travel transverselyrelative to a longitudinal axis of said assembly and said extractorstravel perpendicularly relative to the travel of said pins.
 2. Theassembly of claim 1 wherein each said latch pin includes a cross pintherethrough, and wherein said cross pin compresses said spring againsta wall of said bracket as said cam cams against said cross pin.
 3. Theassembly of claim 2 wherein said cam has a cam surface which is a ramp.4. The assembly of claim 3 wherein said latch lever is pivotallyconnected to said snowplow frame, said assembly further including firstand second linkages connected between said latch lever and saidextractors.
 5. The assembly of claim 4 wherein each of said first andsecond linkages includes a linkage arm connected to said latch lever,and a linkage rod pivotally connected on a first end to said linkage armand connected on a second end to said extractor.
 6. The assembly ofclaim 5 wherein said latch lever includes a connecting rod extendingtransversely of said snowplow frame, said first and second linkagesbeing connected to said connecting rod.
 7. The assembly of claim 1wherein said first and second arms are part of said mount frame and saidfirst and second receivers are part of said snowplow frame.
 8. Theassembly of claim 1 further comprising a plow blade mounted on a forwardend of said A-frame.
 9. The assembly of claim 8 further comprising: alift cylinder connected between said lift frame and said A-frame; andstructure connecting said lift frame and said plow blade, saidconnecting structure including resilient and non-resilient portions;said resilient portion creating slack in said non-resilient portion whensaid plow blade is dropped to the ground and pressure is released fromsaid lift cylinder thereby permitting said lift frame to be rotatedrelative to said A-frame toward said mount frame.
 10. The assembly ofclaim 9 wherein said connecting structure resilient and non-resilientportions comprise a tension spring and a chain respectively.
 11. Theassembly of claim 9 wherein said connecting structure resilient andnon-resilient portions comprise a tension spring and a cablerespectively.
 12. A snowplow and mount assembly comprising: a mountframe adapted to be secured to a vehicle having a longitudinal axis; asnowplow frame including a lift frame and an A-frame pivotally connectedto said lift frame on a rearward end of said A-frame; one of said mountframe and said lift frame having first and second arms and the other ofsaid mount frame and said lift frame having first and second receivers,said first and second receivers receiving said first and second arms,respectively upon relative movement therebetween in a directiongenerally parallel to the longitudinal axis of the vehicle; first andsecond latch pins normally biased toward a latched position, respectiveones of which removably secure said first and second arms in said firstand second receivers; and a latch lever operably associated with saidfirst and second latch pins for permitting both said latch pins to moveto the latched position and for moving both said latch pins to anunlatched position; further comprising: said snowplow frame including ajack stand moveable to and between an extended ground contacting andsnowplow frame supporting position and a retracted ground noncontactingand snowplow frame nonsupporting position; said latch lever operablyfreeing said jack stand for movement into the extended position whensaid latch pins are in the unlatched position and operably preventingjack stand movement maintaining said jack stand in the refractedposition when said latch pins are in the latched position.
 13. Theassembly of claim 12 wherein said jack drops by gravity before saidlatch pins unlatch.
 14. The assembly of claim 12 further comprisingfirst and second jack stand locks, said first lock preventing relativemovement of said jack stand relative to said snowplow frame when saidjack stand is in the extended position and said second lock preventingrelative movement of said jack stand relative to said snowplow framewhen said jack stand is in the refracted position.
 15. The assembly ofclaim 14 wherein said first jack stand lock comprises: a jack stand locklever having an aperture therein through which a leg of said jack standpasses; and a spring biasing an edge of said lock lever aperture intocontact with said jack stand leg; said spring and lock lever normallypreventing upward movement of said jack stand relative to said snowplowframe while permitting downward movement of said jack stand relative tosaid snowplow frame, whereas pivoting said lock lever against the biasof said spring frees said jack stand leg from said lock lever apertureedge thereby permitting upward movement of said jack stand relative tosaid snowplow frame.
 16. The assembly of claim 14 wherein said secondjack stand lock comprises: a jack stand lock pin movable into and out ofan aperture in a leg of said jack stand; and a spring biasing said lockpin toward said jack stand leg; said spring and lock pin normallypreventing downward movement of said jack stand relative to saidsnowplow frame, whereas urging said lock pin against the bias of saidspring frees said jack stand leg from said pin permitting downwardmovement of said jack stand relative to said snowplow frame.
 17. Theassembly of claim 16 wherein said jack stand drops by gravity to theextended position when said jack stand leg is freed from said pin. 18.The assembly of claim 16 wherein said latch lever includes a camoperably connected thereto and said jack stand lock pin is fixed to acam follower which cooperates with said cam such that pivoting saidlatch lever to move said latch pins to the unlatched position urges saidcam follower and hence said jack stand lock pin against the bias of saidspring and away from said jack leg and out of said aperture thereof,whereas pivoting said latch lever to permit said latch pins to move tothe latched position permits said spring to bias said jack stand lockpin toward said jack stand leg and into said aperture thereof.
 19. Theassembly of claim 18 wherein said latch lever includes a connecting rodextending transversely of said snowplow frame, said cam is a cylinderencircling said connecting rod and fixed thereto and said cam followeris a cylinder encircling said connecting rod and slidable relativethereto.
 20. The assembly of claim 19 wherein said cam cylinder and camfollower cylinder have mating arcuate cam surfaces.
 21. The assembly ofclaim 12 further comprising: a spring biasing each said latch pin intosaid latched position; and a pin extractor associated with each saidlatch pin and actuatable by said latch lever to extract said latch pinfrom said arm and against the bias of said spring.
 22. The assembly ofclaim 21 wherein said extractor includes a cam which operably camsagainst said latch pin during extraction thereof.
 23. The assembly ofclaim 22 wherein each said latch pin and respective extractor aremounted in brackets mounted to said snowplow frame, said bracketsguiding movement of said latch pin and extractor.
 24. The assembly ofclaim 23 wherein said latch pins travel transversely relative to alongitudinal axis of said assembly and said extractors travelperpendicularly relative to the travel of said pins.
 25. The assembly ofclaim 24 wherein each said latch pin includes a cross pin therethrough,and wherein said cross pin compresses said spring against a wall of saidbracket as said cam cams against said cross pin.
 26. The assembly ofclaim 25 wherein said cam has a cam surface which is a ramp.
 27. Theassembly of claim 26 wherein said latch lever is pivotally connected tosaid snowplow frame, said assembly further including first and secondlinkages connected between said latch lever and said extractors.
 28. Theassembly of claim 27 wherein each of said first and second linkagesincludes a linkage arm connected to said latch lever, and a linkage rodpivotally connected on a first end to said linkage arm and connected ona second end to said extractor.
 29. The assembly of claim 28 whereinsaid latch lever includes a connecting rod extending transversely ofsaid snowplow frame, said first and second linkages being connected tosaid connecting rod.
 30. The assembly of claim 19 wherein said first andsecond arms are part of said mount frame and said first and secondreceivers are part of said snowplow frame.
 31. The assembly of claim 19wherein said snowplow frame comprises a lift frame and an A-framepivotally connected to said lift frame on a rearward end of saidA-frame.
 32. The assembly of claim 31 further comprising a plow blademounted on a forward end of said A-frame.
 33. The assembly of claim 32further comprising: a lift cylinder connected between said lift frameand said A-frame; and structure connecting said lift frame and said plowblade, said connecting structure including resilient and non-resilientportions; said resilient portion creating slack in said non-resilientportion when said plow blade is dropped to the ground and pressure isreleased from said lift cylinder thereby permitting said lift frame tobe rotated relative to said A-frame toward said mount frame.
 34. Theassembly of claim 33 wherein said connecting structure resilient andnon-resilient portions comprise a tension spring and a chainrespectively.
 35. The assembly of claim 33 wherein said connectingstructure resilient and non-resilient portions comprise a tension springand a cable respectively.
 36. A method of attaching a snowplow frame toa mount frame comprising: providing a mount frame secured to a vehicleand a snowplow frame, the vehicle having a longitudinal axis, thesnowplow frame including a lift frame and an A-frame pivotally connectedto the lift frame on a rearward end of the A-frame; one of the mountframe and the lift frame having first and second arms and the other ofthe mount frame and the lift frame having first and second receivers,the first and second receivers receiving the first and second arms,respectively upon relative movement therebetween in a directiongenerally parallel to the longitudinal axis of the vehicle; one of themount frame and the lift frame having first and second latch pinsnormally biased toward a latched position, respective ones of whichremovably secure the first and second arms in the first and secondreceivers, and having a lever operably associated with the first andsecond latch pins for permitting both of the latch pins to move to thelatched position; a spring biasing each latch pin into the latchedposition; a pin extractor associated with each latch pin and actuatableby the latch lever to extract the latch pin from the arm and against thebias of the spring; the extractor including a cam which operably camsagainst the latch pin during extraction thereof; each latch pin andrespective extractor being mounted in brackets mounted to the snowplowframe, the brackets guiding movement of the latch pin and extractor;wherein the latch pins travel transversely relative to a longitudinalaxis of the assembly and the extractors travel perpendicularly relativeto the travel of the pins; effecting relative movement between the mountframe and the snowplow frame in a direction generally parallel to thelongitudinal axis of the vehicle so that the receivers receive the armstherein; and operating the lever to permit both of the latch pins tomove to the latched position.
 37. A method of detaching a snowplow framefrom a mount frame comprising: providing a mount frame secured to avehicle and a snowplow frame removably attached to the mount frame, thevehicle having a longitudinal axis, the snowplow frame including a liftframe and an A-frame pivotally connected to the lift frame on a rearwardend of the A-frame; one of the mount frame and the lift frame havingfirst and second arms and the other of the mount frame and the liftframe having first and second receivers, the first and second receiversreceiving the first and second arms, respectively upon relative movementtherebetween in a direction generally parallel to the longitudinal axisof the vehicle; one of the mount frame and the lift frame having firstand second latch pins normally biased toward a latched position,respective ones of which removably secure the first and second arms inthe first and second receivers, and having a lever operably associatedwith the first and second latch pins for moving both of the latch pinsto the unlatched position; a spring biasing each latch pin into thelatched position; a pin extractor associated with each latch pin andactuatable by the latch lever to extract the latch pin from the arm andagainst the bias of the spring; the extractor including a cam whichoperably cams against the latch pin during extraction thereof; eachlatch pin and respective extractor being mounted in brackets mounted tothe snowplow frame, the brackets guiding movement of the latch pin andextractor; wherein the latch pins travel transversely relative to alongitudinal axis of the assembly and the extractors travelperpendicularly relative to the travel of the pins; operating the leverto move both of the latch pins to the unlatched position; and effectingrelative movement between the mount frame and the snowplow frame in adirection generally parallel to the longitudinal axis of the vehicle sothat the arms move out of the receivers.
 38. A method of detaching asnowplow frame from a mount frame comprising: providing a mount framesecured to a vehicle and a snowplow frame removably attached to themount frame, the vehicle having a longitudinal axis, the snowplow frameincluding a lift frame and an A-frame pivotally connected to the liftframe on a rearward end of the A-frame; one of the mount frame and thelift frame having first and second arms and the other of the mount frameand the lift frame having first and second receivers, the first andsecond receivers receiving the first and second arms, respectively uponrelative movement therebetween in a direction generally parallel to thelongitudinal axis of the vehicle; one of the mount frame and the liftframe having first and second latch pins normally biased toward alatched position, respective ones of which removably secure the firstand second arms in the first and second receivers, and having a leveroperably associated with the first and second latch pins for moving bothof the latch pins to the unlatched position; operating the lever to moveboth of the latch pins to the unlatched position; and effecting relativemovement between the mount frame and the snowplow frame in a directiongenerally parallel to the longitudinal axis of the vehicle so that thearms move out of the receivers; further comprising: the snowplow frameincluding a jack stand movable to and between an extended groundcontacting and snowplow frame supporting position and a retracted groundnoncontacting and snowplow frame nonsupporting position; whereinactuating the lever to move the latch pins to the unlatched positionfrees the jack stand to drop by gravity to the extended position.
 39. Amethod of attaching a snowplow frame to a mount frame comprising:providing a mount frame secured to a vehicle and a snowplow frame, thevehicle having a longitudinal axis, the snowplow frame including a liftframe and an A-frame pivotally connected to the lift frame on a rearwardend of the A-frame; one of the mount frame and the lift frame havingfirst and second arms and the other of the mount frame and the liftframe having first and second receivers, the first and second receiversreceiving the first and second arms, respectively upon relative movementtherebetween in a direction generally parallel to the longitudinal axisof the vehicle; one of the mount frame and the lift frame having firstand second latch pins normally biased toward a latched position,respective ones of which removably secure the first and second arms inthe first and second receivers, and having a lever operably associatedwith the first and second latch pins for permitting both of the latchpins to move to the latched position; a spring biasing each latch pininto the latched position; a pin extractor associated with each latchpin and actuatable by the latch lever to extract the latch pin from thearm and against the bias of the spring; the extractor including a camwhich operably cams against the latch pin during extraction thereof;each latch pin and respective extractor being mounted in bracketsmounted to the snowplow frame, the brackets guiding movement of thelatch pin and extractor; wherein the latch pins travel transverselyrelative to a longitudinal axis of the assembly and the extractorstravel perpendicularly relative to the travel of the pins; effectingrelative movement between the mount frame and the snowplow frame in adirection generally parallel to the longitudinal axis of the vehicle sothat the receivers receive the arms therein; and actuating the lever topermit both of the latch pins to move to the latched position.
 40. Amethod of detaching a snowplow frame from a mount frame comprising:providing a mount frame secured to a vehicle and a snowplow frameremovably attached to the mount frame, the vehicle having a longitudinalaxis, the snowplow frame including a lift frame and an A-frame pivotallyconnected to the lift frame on a rearward end of the A-frame; one of themount frame and the lift frame having first and second arms and theother of the mount frame and the lift frame having first and secondreceivers, the first and second receivers receiving the first and secondarms, respectively upon relative movement therebetween in a directiongenerally parallel to the longitudinal axis of the vehicle; one of themount frame and the lift frame having first and second latch pinsnormally biased toward a latched position, respective ones of whichremovably secure the first and second arms in the first and secondreceivers, and having a lever operably associated with the first andsecond latch pins for moving both of the latch pins to the unlatchedposition; a spring biasing each latch pin into the latched position; apin extractor associated with each latch pin and actuatable by the latchlever to extract the latch pin from the arm and against the bias of thespring; the extractor including a cam which operably cams against thelatch pin during extraction thereof; each latch pin and respectiveextractor being mounted in brackets mounted to the snowplow frame, thebrackets guiding movement of the latch pin and extractor; wherein thelatch pins travel transversely relative to a longitudinal axis of theassembly and the extractors travel perpendicularly relative to thetravel of the pins; operating the lever to move both of the latch pinsto the unlatched position; and effecting relative movement between themount frame and the snowplow frame in a direction generally parallel tothe longitudinal axis of the vehicle so that the arms move out of thereceivers.
 41. A method of detaching a snowplow frame from a mount framecomprising: providing a mount frame secured to a vehicle and a snowplowframe removably attached to the mount frame, the vehicle having alongitudinal axis, the snowplow frame including a lift frame and anA-frame pivotally connected to the lift frame on a rearward end of theA-frame; one of the mount frame and the lift frame having first andsecond arms and the other of the mount frame and the lift frame havingfirst and second receivers, the first and second receivers receiving thefirst and second arms, respectively upon relative movement therebetweenin a direction generally parallel to the longitudinal axis of thevehicle; one of the mount frame and the lift frame having first andsecond latch pins normally biased toward a latched position, respectiveones of which removably secure the first and second arms in the firstand second receivers, and having a lever operably associated with thefirst and second latch pins for moving both of the latch pins to theunlatched position; operating the lever to move both of the latch pinsto the unlatched position; and effecting relative movement between themount frame and the snowplow frame in a direction generally parallel tothe longitudinal axis of the vehicle so that the arms move out of thereceivers; further comprising: the snowplow frame including a jack standmovable to and between an extended ground contacting and snowplow framesupporting position and a retracted ground noncontacting and snowplowframe nonsupporting position; wherein actuating the lever to move thelatch pins to the unlatched position frees the jack stand to drop bygravity to the extended position.